A powerful earthquake struck Nepal Saturday, killing over 1,800 people across a swath of four countries as the violently shaking earth collapsed houses, leveled centuries-old temples and triggered avalanches on Mt. Everest. At a magnitude of 7.9, it was the worst tremor to hit the poor South Asian nation in over 80 years.

At least 1,800 people were confirmed dead in Nepal, according to the police. Another 20 were killed in India, six in Tibet and two in Bangladesh. Two Chinese citizens died at the Nepal-China border. Given the scale of the destruction, the death toll is almost certain to rise, said Home Ministry official Laxmi Dhakal.

The area is a popular destination for Israeli travelers, but so far, it is unknown if there are any Israeli casualties. The Israeli Foreign Ministry said Israel will provide Nepal with humanitarian aid and will also send an aircraft to Nepal to evacuate any Israelis who are interested in returning to Israel at this time.

An avalanche swept the face of Mt. Everest after the massive earthquake struck Nepal, said a senior mountaineering guide, killing at least eight and injuring at least 30 people.

The avalanche apparently struck between the Khumbu Icefall, a rugged area of collapsed ice and snow, and the base camp where most climbing expeditions are, said Ang Tshering of the Nepal Mountaineering Association.

Tshering said details were unclear because communication between the base camp and the rest of the Everest region was intermittent.

Nepal’s Home Ministry said that the 30 people who were injured were at the base camp.

“We are in contact with the embassy in Kathmandu and are trying to get more information about the earthquake, particularly for Israelis. We will update as soon as information becomes available,” Israeli Foreign Ministry spokesman Emmanuel Nachson said.

Laxman Dhimri, the director of a Nepalese tourist agency, said the dimensions of the disaster are beyond comprehension. He told Haaretz over the phone that 400 people were killed in the collapse of one building alone. He added that many people are missing, and that the army is working to rescue people trapped under the rubble and is searching for bodies.

The earthquake also shook several cities across northern India, and was felt as far away as Lahore in Pakistan. The epicenter was 80 kilometers (49 mile) northwest of Kathmandu.

Buildings collapse in Old Kathmandu

Several buildings collapsed in the center of the capital, the ancient Old Kathmandu, including centuries-old temples and towers, said resident Prachanda Sual. Among them was the Dharahara Tower, one of Kathmandu’s landmarks built by Nepal’s royal rulers in the 1800s and a UNESCO-recognized historical monument. It was reduced to rubble and there were reports of people trapped underneath.

Old Kathmandu city is a warren of tightly packed, narrow lanes with poorly constructed homes piled on top of each other.

Sual said he saw people running through the streets in panic. Ambulance sirens blared and government helicopters hovered overhead.

National radio warned people to stay outdoors and maintain calm because more aftershocks were feared. A 6.6-magnitude aftershock hit about an hour after the initial quake.

Dozens of people were gathered in the parking lot of Kathmandu’s Norvic International Hospital, where thin mattresses had been spread on the ground for patients rushed outside, some patients wearing hospital pajamas, while doctors and nurses were treating people. A woman with a bandage on her head sat in a set of chairs pulled from the hospital waiting room.

Doctors and nurses had hooked up some patients to IV drops in the parking lot, or were giving people oxygen.

The Kathmandu Valley is densely populated with nearly 2.5 million people, and the quality of buildings is often poor.

The U.S. Geological Survey revised the magnitude from 7.5 to 7.9 and said the quake hit at 11:56 A.M. local time (6:11 A.M. GMT) at Lamjung a shallow depth of 11 kilometers. An earthquake’s magnitude increases by 10 times with each increase in the number. A magnitude 7 quake is capable of widespread and heavy damage while an 8 magnitude quake can cause tremendous damage.

The sustained quake also was felt in India’s capital of New Delhi. AP reporters in Indian cities of Lucknow in the north and Patna in the east also reported strong tremors.

Nepal suffered its worst recorded earthquake in 1934, which measured 8.0 and all but destroyed the cities of Kathmandu, Bhaktapur and Patan.